Wk 2: joint & ligaments Flashcards
Arthrology & hip joint
Joint
union between two or more bones
Fibrous
Fibrous tissue joins the bones
Amount of movement depends on length of fibres
Suture (fibrous)
- Only found in the skull
- Bones are linked by short fibres of connective tissue
- Little to no movement
Joint classification
- Structure: fibrous, cartilaginous and synovial
- Amount of movement available: immobile, slightly mobile and freely mobile
Syndesmosis (fibrous)
- Forearm & leg
- Bones are linked by longer bands of connective tissue
- Very slightly mobile
Cartilaginous
Cartilage tissue joins the bones
Amount of movement depends on the type of cartilage
Symphysis or secondary cartilaginous
- A disc of fibrocartilage binds 2 bones together
- Found in the mid-line of the body
- Slightly mobile
First sternocostal joint (Synchondrosis)
- Very limited mobility
Synovial
Bones lined with cartilage (joint cavity)
Amount of movement depends on the shape of the joint
Synchondrosis or primary cartilaginous
- Found at epiphyseal plates (where bone growth occurs)
- Eventually completely ossify
- Epiphyseal line & immobile
Synovial joint classification
- Shape
- Degrees of freedom (uni, bi, multiaxial)
Joint axes (synovial)
- Anteroposterior: front to back
- Horizontal: side to side/left to right
- Longitudinal: vertical or along length of bone
Degrees of freedom (synovial)
Number of axes about which movement occurs
Uniaxial: one pair of movements
Biaxial: two pairs of movements
Multiaxial: three pairs of movements
Axis is perpendicular to the plane (of body) (synovial)
- Sagittal perpendicular to horizontal
- Coronal perpendicular to anteroposterior axis
- Transverse perpendicular to longitudinal axis
Movement axes and their movements possible (synovial)
- Longitudinal: rotation
- Anteroposterior: abduction/adduction and lateral flexion
- Horizontal: flexion/extension
Ligaments
bands of fibrous tissue that occur at joints
Ligament functions
- Act as a mechanical constraint
- Prevent undesired movement
- Permit limited amounts of desired movement
- Sensory: proprioception
Types of ligaments
- Intra-capsular: deep to capsule
- Capsular: re-enforces capsule
- Extra-capsular: away from capsule
Bursae
Fluid-filled sacs around many synovial joints: potential space
Function to reduce friction as structures slide on one another thus
Located between layers of muscles
Articular Discs
Fibrocartilage pads between the articular surfaces of some synovial joints
Functions of articular discs
- Shock absorbers
- Permit different movements to occur in the joint
- Aid mechanical fit between articular surfaces
- Restrain movement
- Assist lubrication
Active movement
Produced by muscle contraction
Passive movement
Produced by an external force
Passive movement types
Passive physiological: can also be produced actively
Passive accessory: the movement cannot be produced actively
Roll (roll spin glide)
one surface rolls across the other (contact of new parts of both surface)
Spin (roll spin glide)
one surface spins relative to the other surface around a fixed central axis
Glide (roll spin glide)
one surface slides across the other (contact of new parts of one surface with the same parts of another surface)
Flexion
reduces angle between bones
bend knee back
Extension
increase angle between bones
straighten leg
Abduction
the movement of a bone away from the midline
straight leg moves up on the side
Adduction
the movement of a bone towards the midline
straight leg moves downon the side
Medial/lateral rotation
Movement of bone around longitudinal axis
Circumduction
Flexion, abduction, extension, adduction, and rotation in succession
Inversion
medial movement of sole
Eversion
lateral movement of sole
Dorsiflexion
Bending foot in direction of dorsum (superior surface)
bending foot up
Plantar flexion
Bending foot in direction of plantar surface (sole)
bending foot down
Pronation
Movement of forearm that turns palm posteriorly
Supination
Movement of forearm that turns palm anteriorly.
Ball and socket axes
Multiaxial
Ball and socket movement
All movements
Ball and socket example
Hip and shoulder
Hinge joint axes
Uniaxial
Hing joint movement
Flexion and extension
Hinge joint example
Elbow
Ellipsoid joint axes
Bi axial
Ellipsoid example
Wrist
Condyloid joint axes
Bi axial
Condyloid joint movements
Flexion, extension and slight rotation
Condyloid joint example
Knee and metacarpal
Pivot axes
Uniaxial
Pivot movement
Pronation and supination
Pivot example
neck
Saddle joint axes
Biaxial
Saddle joint movements
Flexion, extension, adduction, abduction
Saddle joint example
Thumb
Plane joint axes
no axial
Plane joint movement
Slight gliding movement
Plane joint example
intertarsal and intercarpal
Hinge joint description
Projection fits into a slot parallel
Condyloid joint description
Oval projection fits into an oval hollow
Pivot joint description
Round process fits within a ring
Saddle joint description
Concave in convex in a cross shape
Ball and socket joint description
Ball fits into a socket